It’s still in a semi-private beta testing, but it’s been possible over the past several days to get a glimpse if you follow the crew on Twitter.

Flickmob is a video version of Turntable.fm, a hot Silicon Valley startup that lets people log into virtual rooms and share music with others as cartoon avatars bop their heads and vote for favorites. In Flickmob, users earn points from the crowd by picking gems from YouTube.

Here’s a shot of me enjoying “Brooklyn We Go Hard” by Jay-Z:

The inspiration came from actually being bona fide power users of Turntable.fm: When they were promoting the Mix-a-Lot Facebook game, Giant Thinkwell came up with the marketing masterstroke of getting Mix-a-Lot himself to guest-DJ in a Turntable.fm room—and the team hacked together a custom avatar that pasted a Mix-a-Lot head onto his character.

The room was quickly flooded to capacity with fans. The combination of Mix-a-Lot’s fame and Giant Thinkwell’s creative promotion got the game a ton of press—including a mention in Jimmy Fallon’s “Late Night” monologue. The number of fans on Mix-a-Lot’s Facebook page exploded from about 1,200 to 21,000 in just one day, Giant Thinkwell CEO Adam Tratt says.

But very few of them were actually digging into the game itself, even though it offered exclusive personal prizes like a ride down Seattle’s Broadway in Mix-a-Lot’s Lamborghini. After all that labor, something wasn’t sticking.

“Our conclusion was, these 21,000 Mix-a-Lot fans, they love him for his personality, they love him for his music, they love him for his exotic cars—but they’re not going to start playing a social game just for the hell of it,” Tratt says. “The question at the end of that was: Do we try to go after a different celebrity that might have a better overlap with the social game demographic? Or do we do something new?”

That something new is Flickmob. Because it’s in a beta test, the bugs are still being worked out—when I played around with it recently, some small navigation things like scrolling weren’t fully functional, and some design and interface elements got squashed together depending on which browser you used.

But the experience itself works, helped along by the distinct design style of Giant Thinkwell co-founder Kyle Kesterson. Giant Thinkwell plans to leverage Kesterson’s illustration talents by assembling “an ensemble of awesome to bizarre avatars” for users to adopt. The videos themselves are from YouTube, piped in through its API. Like Turntable.fm, you sign in with your Facebook account (videos also can be imported from Facebook).

Giant Thinkwell isn’t the only one trying out this idea. A San Francisco Bay Area startup called Chill has also built a Turntable-for-video website/Facebook app (and just got a $1.5 million investment for it, being Silicon Valley and all).

They’re both making a stab at the “Live Web” (or “Alive Web“), a place where people can get together and interact in real time by sharing content and experiences. It’s the next generation of chat rooms, tying together layers of Web platforms like Facebook and YouTube and letting people interact and share.

“We decided that we could easily spend the next year to try and get the right celebrity and the right game and maybe make that work, but that felt to us like that was going to be a less exciting approach than going after the live web,” Tratt says. “It’s something that’s an emerging trend, and we felt like we could contribute in a special way to that.”

There are still elements of the original Giant Thinkwell idea at play in Flickmob, particularly the gamification aspect. While Facebook games were more straightforward, video-sharing opens the door for getting users to stick with the site by offering rewards, both virtual (like new avatars or points) and real, such as sponsored prizes.

Giant Thinkwell’s original focus on celebrities as the target customer has shifted, however. Instead of going after those big fish, the startup hopes to build a system that notable people will use to distribute content and get together with fans—just like Mix-a-Lot, Talib Kweli, or Questlove of the Roots have done with Turntable, or like Snoop Dogg has done with Chill (what is it with the hip-hop stars and social Web startups?).

“Someone’s going to figure out how to do this celebrity thing, but it’s going to be a company based in L.A. that has connections and has access to celebrities,” Tratt says. “For us, access to the celebrities is a function of money, and it didn’t feel like were set up to be the most successful company on the planet.”

Giant Thinkwell, which was originally hatched at a Startup Weekend, currently has five employees: Tratt, Kesterson, and third co-founder Kevin Leneway, along with Donald DeSantis and Kav Latiolais. The startup announced a $600,000 seed round in June from Madrona Venture Group, Founder’s Co-op and unnamed angels.